Field
This disclosure is generally related to mobile ad-hoc networks (MANETs). More specifically, this disclosure is related to a software-defined MANET based on an intelligent backbone infrastructure.
Related Art
Typical ad-hoc communication systems oftentimes require independent mobile users that can communicate in a non-centralized and self-organized fashion. For example, mobile ad-hoc networks (MANETs) employ peer-to-peer a communication protocol to determine a path between two wireless nodes. Some key characteristics of MANETs include their ability to adapt to route changes due to mobility and the fact that they have no requirement for base stations or access points for node organization.
In theory, a MANET provides an ideal communication infrastructure to support disaster-relief and battlefield operations, emergency search and rescue missions, and many other mobile and distributed applications. However, these applications cannot be supported effectively in today's networks. This is mainly because the networks don't scale due to the excessive signaling incurred with an increasing number of nodes and applications. More specifically, MANET protocols distribute calculations (such as routing information) over many nodes hop-by-hop. To ensure protocol correctness and efficient operation, such as to avoid loops and excessive flooding, complex distributed algorithms are needed.
On the other hand, cellular systems use centralized resources (such as a set of networked cell towers) to service large areas, usually at much lower data rates than a MANET could achieve to nearby neighbors. However, compared to the distributed system, this centralized system allows much simpler routing and protocol operations due to the centralized nature of the system.
The centralized nature can also be seen in software-defined networking (SDN), such as the one based on the OpenFlow protocol. In SDN, the “control plane” and the “data plane” are separated, and at least two control routers are used to instantiate state on the controlled network elements. With SDN, the topology of the network is virtualized at the controller nodes, which compute routes from sources to destinations according to a network-wide view, and can instantiate the “flow-state” at each switch of the network. Unfortunately, current SDN implementations compute paths based on the network's flow-states, and thus cannot be applied to MANETs.